System Service has started preorders for a second series of MGS4 Ration Sound Keychains which feature another set of six toys that emit sounds and phrases from the Metal Gear Solid 4 game. The character voices captured are: "Old Snake A," "Old Snake B," "Otacon," "Raiden," and "Liquid Ocelot." We were hoping for a Ration Sound Keychain that blares out Old Snake's "cough-hack-cough" sound effect but maybe next time. To listen to any of the sound effects, users simply press the button on the front of each keychain.